In the past, set-top box referred to an analog channel adder or an analog channel descrambler on the basis of a cable television network. Along with the rapid development of the digital video broadcasting and Internet, there is an increasing demand on information, and the set-top box has gradually become a device for receiving and processing the information, with a television as a display terminal.
Currently, there are various set-top boxes available in the market. For example, depending on the types of the received signals, the set-top boxes may include analog set-top boxes and digital set-top boxes, and depending on the signal transmission networks, the set-top boxes may include satellite transmission set-top boxes, optical cable set-top boxes and terrestrial transmission set-top boxes. Most of these set-top boxes are merely used to receive and process image signals and audio signals, and some of them may be used to provide limited interactive services, e.g., to show a desired advertisement to a user in accordance with his preferences.
However, along with the improvement of the living standard and the development of the communication and network technologies, it is insufficient for the sep-top boxes, which merely has a function of receiving and processing the image signals and the audio signals, to meet the user's demands and improve the user experience.